Google has ended a free version of its Google Apps online application suite for small businesses, saying it wants to provide a stronger and more uniform experience to users.

The Internet giant said Thursday in a blog post that now even small businesses with 10 or fewer users will have to pay to use its online app platform, a group that up until now has been free. All businesses will now be charged US$50 per user, per year, for the service.

Google Apps will remain free for individual users, as well as existing business customers that currently use the free version.

"Google Apps for Business," the company's paid offering, provides its email, calendar and online office suite as an all-in-one service, allowing them to be used on private domain names and adding features such as 24-hour phone support. It also offers features such as an archiving service and additional storage for extra fees.

The company doesn't release user numbers for the service, but said last year in a blog posting it had over 40 million users, although the majority of those are believed to be non-paying. Google competes with Microsoft's "Office 365" online service, which offers an email service and online versions of its Word, PowerPoint and Excel programs from $6 per user, per month, which are increasingly integrated with the standard software versions.

A blog post Thursday by Clay Bavor, director of product management for Google Apps, said the service is used by "millions of businesses." Bavor said eliminating the free version will help remove confusion about Google's different offerings and provide a better experience for its business customers, who "quickly outgrow the basic version."

Google has also worked to leverage its other properties to woo corporate customers. This includes offerings such as a service that lets businesses publish mobile Android apps for internal use on their own version of the Google Play online store, as well as online storage that scales up to thousands of terabytes.

Since launching a paid version of its online product in 2007, Google has gradually scaled down the size of businesses that can use it free of charge. In 2009, the limit was set at 50 users, and in 2011 it was lowered to 10 users, prior to ending the free portion of the service.